#include <stdio.h>

int push(int* a, int top, int elem){
    a[++top] = elem;
    return top;
}

int pop(int* a, int top){
    if(top == -1){
        printf("空栈\n");
        return -1;
    }
    printf("弹栈元素：%d \n", a[top]);
    top--;
    return top;
}

int main()
{
    int a[100];
    int top = -1;
    top = push(a, top, 1);
    top = push(a, top, 2);
    top = push(a, top, 3);
    top = push(a, top, 3);
    top = pop(a, top);
    top = pop(a, top);
    top = pop(a, top);
    top = pop(a, top);
    pop(a, top);



    return 0;
}